I'm arriving at the conclusion that there is a 'maximum' distance for taking pictures of birds at with the 200-500, beyond which they aren't worth cropping & keeping. Obviously a lot of factors involved but...
...looking at the file info schema tab in Elements 10, I find a row that says Approximate focus distance: 237/10.
What does that mean? 23.7m or what?
The lens is listed as 2000/10 5000/10 56/10 56/10 - so you see my logic. And I was about 60-odd feet from the subject - at a guess